Work supporting table for machine tools



Jan. 2, 1951 E. E. HosEA- WORK SUPPORTING TABLE FOR MACHINE TOOLS '2 Sheets-Sheet 1 Filed April 5, 1947 faverebb" 6 Q-OSQO.

Q4 rronmsyq Jan. 2, 1951 E. E. HOSEA 2,536,937

WORK SUPPORTING TABLE FOR MACHINE TOOLS Filed April 5, 1947 '2 Sheets-Sheet 2 fvzg 25 v 62 iNVENTOHH Everett 6. Q-(Oaeo; Mm @104 W w, 7 dJ-r-romax-J Patented Jan. 2, 1951 WORK SUPPORTING TABLE FOR MACHINE TOOLS Everett E. Hosea, Kaukauna, Wis., assignor to Kaukauna Machine Corporation, Kaukauna, Wis., a corporation of Wisconsin Application April 3, 1947, Serial No. 739,196

6 Claims. 1 o

The invention relates generally to machine tools, and more particularly to table structures for supporting workpieces upon which machining operations are to be performed by such machines.

One object of the invention is to provide a machine tool work table characterized by its ability to handle workpieces which differ widely in size and shape, and capable of holding such workpieces in the position best suited for the machining operations to be performed.

Another object is to provide a structurally independent work supporting table of the indexing type which may be readily associated with different machine tools, and variously positioned with respect thereto in accordance with the requirements of the particular work involved.

It is also an object of the invention to provide a work supporting table having stationary and indexable work supporting sections adapted to be used together or independently, as required.

Other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiment illustrated in the accompanying drawings, in

which:

Figure 1 is a perspective view of a work supporting table embodying the features of the in--' vention.

Fig. 2 is a transverse sectional view taken in a vertical plane substantially through the center of the table. 7 c

Fig. 3 is a fragmentary sectional view of the table showing the means for frictionally clamping the indexable section in set positions.

Referring to the drawings, the work support-- ing table comprises generally a rigid base or bed' 5 adapted to be mounted adjacent a machine tool, as, for example, a floor type horizontal boring, drilling and milling machine (not shown). The bed 5 is preferably constructed as a well ribbed iron casting, and comprises upright front and back walls 6 and I, end walls 8 and 9, and a horizontal top wall it. As shown in Fig. 1, the top wall 10 of the bed is formed with a central recess II for the accommodation of .a circular platen l2 supported for rotary indexingmovements about a vertical axis. V

In accordance with the invention, the platen i2 is arranged with its upper surface flush with. the corresponding surfaceof the top wall-1010f the bed. The latter is smoothly finished and. thus, together with the platen, provides a horizontal work supporting surface substantially coextensive with the bed 5 and capable ofefiec tively supporting relatively large workpieces.

Smaller workpieces may be supported on the stationar portion of the surface provided by the top wall It! or on the rotatable platen i2 which may be indexed to present different sides of the workpiece for action by the tool of the machine with which the table structure is associated.

' The utility of the improved table structure is further increased by finishing portions of the end walls 8 and f the bed 5 to provide vertical work supporting surfaces at opposite ends of the bed. This enables the table to accommodate workpieces which cannot be supported conveniently on a horizontal surface and also workpieces which, because of their shape or for other reasons, require both horizontal and vertical supporting surfaces.

As will be seen by reference to Fig. 1 of the drawings, the various work supporting surfaces of the table are constructed to facilitate the clamping of the workpieces thereto. Thus, the two end sections of the top wall Ii! are formed with parallel upwardly opening T-slots L3, in this instance extending longitudinally of the bed 5, The face of the platen I2 is likewise formed with parallel T-slots hi, preferably spaced apart similarly to the T-slots l3 so that they may be alined therewith when the platen is set in the position shown in Fig. 1. Parallel T-slots [5 in the'end walls 8 and 9 are preferably disposed horizontally. The top ill of the bed ma also be formed with a series of holes It between the grooves [3 for the reception of dowell pins or the like by which conventional stops, positioning fixtures, etc. are adapted to be held in place on the table.

In the exemplary work supporting table, the recess I l in the table top is formed with a diameter slightly greater than the width of the bed 5, thus leaving it open at the front and back and bordered at opposite ends by arcuate walls 20. The recess is closed at the bottom by a horizontal wall 2! reenforced by transverse upright webs 22 extending between the front and back walls 6 and i and by spaced upright webs to rotate. Referring now to Fig. 2 of the drawings, the

platen i2 in its preferred form comprises a circu lar-casting of a diameter corresponding approximately to the Width of the table, suitably ribbed on its under side to provide strength and rigidity. and formed with a depending central tubular hub adapted to receive the upper end of the stud 26. In the particular embodiment illustrated, the platen I2 is journaled on the stud 26 through the medium of radial and end thrust bearings 3| clamped between an inwardly projecting shoulder 32 formed in the lower end of the hub 3!) and a nut 33 threaded on the stud 26.

The peripheral surface of the platen I2 is smoothly finished to provide a generally cylindrical frictional clamping surface, and itslower marginal edge portion is turned inwardly to'fcrm a relatively wide peripheral fiange35. Thelower surface of the flange 35 is shapedfor coaction with suitable anti-friction bearings provided-for that purpose within an annular recess 36 in which is seated an annular bearing race 31 of hardened steel. The horizontal wall 21 of the bed is formed with a similar annular recess 38 for the accommodation of a hardened steel race ring 39. Roller elements, such as balls 46, interposed betweenthe bearing race rings serve to support the weight of the platen l2 and the load carried thereby. Intheparticular table illustrated, the roller elemerits 55 comprise ball bearings and are preferably arranged in a plurality of concentricgroups.

For accurately locating the platen l2 in selected indexed positions, a series of suitably spaced locating sockets a: areprovided on the platen. The sockets are arranged concentrically in series about the axis of the table in the outer portion of the flange 35 and are fitted with hardened steel bushings 42. The adjacent portion of-the flange 355 is finished on the underside :1.-

with a plane surface adapted to slide across the upper end of a cylindrical boss 43 integrally formed on the front wall 6 of the bed and having a bore 44 normal to the surface of the platen l2 for the accommodation of a hardened steel plunger 45 which is guided for axial movement in a'bushing 6 fitted in the bore. 'A spring 41 interposed between the lower end of the plunger 45 and a screw plug is threaded into'the lower end of the bore d5 urges the plunger upwardly so as to enter it into the locating sockets 4| when the table is turned to the corresponding indexed positions. The plunger thus accurately located the platen in its indexed position and effectually locks it in place.

Manually operable means is provided forretracting the plunger 35 to permit the platento be indexed. For this purpose, the plunger' i5 is formed with rack teeth 59 coacting with a'pinion 5U rigid with or formed on a stub shaft '5! journaled in the boss 43 and extending transversely of the bore 44. At its outerend the shaft 5! is provided with a hand lever 53 by which'it may be rotated to retract the p1unger'46 against the action of the spring 41.

Provision is made for frictionally clamping the table in indexed positions to relieve the strain on the locating plunger 45 when the table structure is in use. For this purpose, a pair of arcuate- 1y faced shoes 55 (Figs. 1 and 3) are supported for engagement with the peripheralsurface of the platen l2 on opposite sides of the plunger. As shown in Fig. 3, each shoe is supported-on the inner end of a clamping screw 56 threaded in a recess 59 in the arcuate wall 20 of the bed acts to prevent rotation of the shoe when the theinvention provides a work supporting table "of novel and advantageous construction. provision of -a horizontal working surface, including stationary and indexable portions, ren- The clers the table universally adaptable for handling iarge 'workpiecesand also workpieces upon which machining operations are to be performed on different sides. The provision of vertical work supporting-surfaces at the ends of the bed enables the structure to accommodate workpieces which cannot be supported conveniently in a horizontal position and also angular workpieces which require support in two different planes. The improved table thus greatly facilitates the performance of rnachin-ing operations by large floor-type machine tools.

--I-claim as my invention:

-l; Aworksupporting table comprising, incombination, anelongatcd box-like bed having integral side, end-and top walls, a circular platen, said -top wall being-recessed centrally to receive said platen'with its-upper surface flush with the tcp-wallof the bed, said platen and said top wall being for-med with upwardly opening T-slots for clamping workpieces thereto, longitudinal and transverse webs within said bed supporting '11 rigid bearing for said platen at the bottom of and centrally disposed within said recess, said bearing -including'an upright stud engaging in a bearing recess in said-platen, an integral boss on one sidewallofthe beddisposed adjacent said recess with one end'underlying saidplaten, said boss having a bore normal to the iower surface of the platen, a plunger in said bore, a piurality of downwardly opening locating sockets in the platen= for receiving said plunger to locate the platen in successive indexed positions, spring means yieldably urging said plunger into the socket located in operative relation therewith, and manually operable means for retracting theplunger to release the platen for indexing-movement.

-A work supporting table comprising, in combination, an'el'ongated 'boxlike bed'having integral side-end and top walls, a circular platen, said topwall-being recessed centrally to receive said platen with its upper surfacefiush with the top wall of thebed,- said platen and said top wall being formed with upwardly opening T-slots for clamping'workpieces thereto, longitudinal and transverse *webs within said be'd supporting a rigid bearing for said platen-at the bottom of and centrally disposed within said recess, said'bearing including an upright stud engaging in a bearnigreces's in said'platen, an integral boss on one sidewall of the bed disposedadjacent said recess with one end underlying said platen, said boss having a bore normal to thelower surface of the platen, a plunger in said bore, a plurality 'of downwardly opening locating sockets in the platen 'for" receiving said plunger'to locate the platen in successive indexed positions, means for shifting' said plunger into and out of engagement with the socketsi meansiorrigidly'clainping said plat- 5 en in set positions including a pair of arcuate shoes frictionally engaging the peripheral surface of the platen, and adjusting screws for said shoes threaded in the side wall of said bed on opposite sides of said recess.

3. A work supporting table comprising, in combination, an elongated box-like bed having integral side, end and top walls, a circular platen of a diameter corresponding to the width of the bed, said top wall having a central recess dividing it into two separate sections spaced apart to receive the platen therebetween, the side walls of said bed being open adjacent said recess to provide convenient access to the platen, means supporting said platen with its upper surface flush with the surfaces of saidtop Wall sections and for rotation about an axis perpendicular to such surfaces, said top wall sections and said platen being smoothly finished to provide a horizontal work supporting surface substantially coextensive with the horizontal section of the bed, and frictional clamping shoes supported on said bed at opposite sides of the opening in said front wall engageable with the peripheral surface of said platen to clamp the same rigidly in set positions.

4. A work supporting table comprising, in combination, an elongated box-like bed having integral side, end and top walls, a circular platen, said top wall and said side walls being recessed centrally to receive said platen with its upper surface flush with the top wall of the bed, said platen, said top wall and the ends walls of said. bed being finished to provide flat work supporting surfaces and having T-slots formed therein for clamping workpieces thereon, and supporting flanges formed on said side and end walls adjacent their lower edges, said flanges being apertured for the reception of hold down bolts and said walls being recessed adjacent the flanges to provide clearance for the bolts.

5. A work supporting table comprising, in combination, an elongated generally rectangular bed having a horizontal work supporting surface on its upper side with a central recess formed therein, a horizontal wall defining the bottom of said recess, a cylindrical stud projecting up- Wardly from said wall and substantially centered in said recess, a circular platen journaled on said stud with its upper surface flush with the work supporting surface of the bed, a circular bearing track formed in the lower face of said platen, a correspondingly dimensioned circular bearing track formed on the upper face of said wall, and anti-friction bearings interposed between said bearing tracks, including a pair of hardened steel rings and roller elements arranged in a plurality of concentric rows and disposed between said rings to complete the bearing relationship.

6. A work supporting table comprising, in combination, a generally rectangular bed having a horizontally disposed top with a central recess therein, a circular platen supported in said recess for rotation about a vertical axis, said platen having its upper surface disposed flush with the upper surfaces of said top to provide a plane horizontal work supporting surface coextensive with the top of said bed, and upright Walls at opposite ends of said bed providing plane vertical work supporting surfaces, said top, said upright walls and said platen being formed with T-slots for clamping workpieces thereto.

EVERETT E. HOSEA.

REFERENCES CETED The following references are of record in the file of this patent:

UNITED STATES PA'IENTS Number Name Date 162,841 Mayer May 4, 1875 1,956,883 Vanderber May 1, 1934 2,114,911 Burt Apr. 19, 1938 2,363,383 Bertoldo et a1 Nov. 21, 1944 

